The impact factor (IF) or journal impact factor of an academic journal is a measure reflecting the yearly average number of citations to recent articles published in that journal. It is a parameter related to journals and it is calculated through simple calculation for citation per article [i.e total citations/total articles] for a period of mainly two years [not fixed, for some journals 5 years IF are also there].
The h-index is defined as the maximum value of h such that the given author/journal has published h papers that have each been cited at least h times. It is parameter related t productivity of a researcher. For example, any researcher's H-index 45 means among his/her total research articles 45 articles have at least 45 citations.
For checking of IF you may go for Clarivate Analytics [Thomson Reuters].